An anonymous reader writes: Mozilla has put up a blog post about how building a paid app will work for Firefox OS. The Firefox Marketplace will host web apps, and Mozilla is quick to point out that the apps won't lock you into Firefox OS. They will use the receipt protocol, which other devices can support. 'There is, of course, a chicken vs. egg problem here so Mozilla hopes to be the egg that helps prove out the decentralized receipt concept and iterate on the protocol. Mozilla invites other vendors to help us work on getting receipts right so that paid apps are as portable and "webby" as possible.' Mozilla has a JavaScript API for exposing device receipts, and a client-side library can then contact a verification service URL from the receipt.Link to Original Source